New developments on the role of intramuscular connective tissue in meat toughness.

Intramuscular connective tissue (IMCT) forms a series of continuous networks integrating muscle fibers and fascicles into a whole organ. The contributions of IMCT to cooked meat toughness have long been recognized. This review concentrates on (a) the potential to manipulate IMCT in the growing animal, (b) postmortem effects on structure and properties of IMCT, and (c) developments in techniques to quantify IMCT in meat. A new hypothesis can explain why IMCT is enzymatically degraded in postmortem aging; however, after cooking, no differences are seen in the IMCT contribution to toughness. This hypothesis proposes that heat-insoluble collagen occurs in a weak pool and a strong pool, where the weak pool is most easily degraded by both proteolysis and heat. Far from being a constant background feature, the IMCT contribution to cooked meat toughness can be varied and deserves fresh research on how to achieve this.